Pneumatic horn



W. A. GARRATT.

PNEUMATIC HORN.

APPLICMION FILED Aumsn 1921.

1 ,427,28 1 Patented Aug. 29, 1922.

Wyn 70m tJNllED STATES PATENT OFFICE.

WALTER A. GARRATT, OF COVI'JSTGHION, KENTUCKY.

PNEUMATIC HORN.

Mamet.

To all whom it may concern:

Be it known that I, WALTER A. '-GARRA TT, a. citizen of the United States, and a resident of Covington, in the county of Kenton and State of Kentucky, have invented certain new and useful Improvements in Pneumatic Horns, of which the following is a fulL-clear, and exact description, reference being had to the accompanying drawings, fprming part of this specification.

My invention relates to sounding devices operated by air pressure or suction, the present invention dealing more particularly with forms adapted to be operated by suction such as is present in the intake manifold oi an automobile engine.

T have devised other varieties of sounding device, some of which have been made the basis of applications for patent, anad the present invention involves the consoli ation of various principles of said previous applications, together with a considerable simplification of structure.

It is my object in the present invention to make a horn, which will give a sound of distinctive nature under very little suction, and to make as simple as possible a structure, which will be adaptable for this purpose.

Among other objects are the production of a sound by the employment of a sound producing vibratory member as the carrier of a valve which finds its seat against another sound producing member and the projection of both sounds into a suitable projection device.

I also produce a sound by the interruption of a current of air, this being the chief sound carried and amplified by the valve carrying member.

Thus the sound produced by the hammering of the valve against the seating member and the sound caused by the interruption of a current of air as transferred through said valve carrying member and also through the support for the valve, combine to give a musical and resonant noise, which is believed to be especially adapted for signal purposes in motor vehicle or boat, or for any warning signal of the size and capacity desired.

The above objects and other advantages which will be noted, I accomplish by that certain construction and arrangement of parts to be hereinafter more specifically pointed out and claimed.

Specification of Letters Patent. Patented A 29 1922 Application filed August 31, 1921. Serial No. 497,201.

In the drawings,

Figure 1 is a side elevation of my improved horn. v

Figure 2 is a central longitudinal section 5 terial, such as thin steel, which closes oil the upper end of the conical extension. Mounted over the diaphragm is a cylindrical cap piece or cover 5 with an out-turned flange and the diaphragm is securely bolted in place by bolts 6 through the flange and the conical extension of the horn.

The cap piece is provided with a comparatively thick and solid partition 7 with a central boss 8 in which is screw-threaded a thimble 9.

This thimble carries at its lower end a vibratory member 10 formed of a pair of resllient sheet metal disks soldered or secured together at their peripheries and separated sufficiently to form a hollow bellows-like member with a central opening 11 in the lower disk portion surrounded by a ring 12 which acts as a valve and takes its seat on the diaphragm 4. The thimble 9 has a central passageway 13 opening through the thimble into, the hollow vibratory member, the opening being controlled by a needle valve 14, the stem of which extends up through a suitable fitting 15 in the head of the cover where the valve is under control of the operator.

Secured to the rear portion of the horn is a coupling 16 through which connection is made by the pipe 17 with the intake manifold of an engine or some desired source of pneumatic suction power. This coupling 16 is connected by nipple 18 and pipe. 19 with an inlet coupling 20 into the interior of the cap 5, where the suction of the intake manifold acts on the vibratory member 10 through the needle valve 14. The inlet port 21 into the vibratory member controlled by the needle valve is much smaller in diamethe instant the disks of the vibratory member are compressed and thevalve 12 lifted from its seat on the diaphragm 4, the vacuum is instantly relieved, causing a ver rapid vibration of the two disk plates ma ing up the vibratory member. This difi'erence in area between the suction inlet and the outlet is an important feature in compelling a rapid vibration.

The vibratory member thus hums under the intake suction giving forth a resonant and musical noise. The valve ring 12 alsocauses a rapid vibration on the diaphragm 4, which augments and intensifies the sound produced by the horn.

In order to permit the free escape of the sound from the vibratory member, the diaphragm 41- is provided with a series of open ings 22 cut in the diaphragm around the .central portion of the disk and further to add to the sound I prefer to secure to the under surface of the diaphragm anopen cylindrical tube or collar portion 23.

Thus a compound sound of peculiar quality will be projected through the horn, and

because of the bellows-like device and its extreme sensitiveness, a very weak suction, such as may be set u in the mouth, will serve to produce considerable sound, while in use with an intake manifold or some pneumatic system there will be a loud, startling, but not unpleasant sound, which is excellently adapted for warning purposes.

While there may be many departures from the exact structure described above, I do not desire that my claims that follow be limited because of my failure to describe them, since I have endeavored merel to show and describe a simple and effective embodiment of my invention, which has proven its value through extended trial.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is v 1.- Ina sounding device, the combination of a shallow vibratory member with resilient top and bottom walls, means for subjecting said member to pneumatic suction, and a valve to relieve said suction secured to one of said walls and a diaphragm separate from said vibratory member against which said valve seats.

2. In a sounding device, thecombination of a shallow vibratory member with resilient to and bottom walls, means for subjecting Mamet saidmembersto pneumatic. suction, and a valve to relieve said suction secured to one of said walls, a resilient diaphragm against which said valve seats, with openings around the valve seat to allow the sound. from the vibratory member to pass the diaphragm.

3. In a sounding device, the combination of a shallow vibratory member with resilient top and bottom walls, means for subjecting said member to pneumatic suction, and a valve to relieve said suction secured to one of said walls, a resilient diaphragm against which said valve seats, with openings around the valve seat to allow the sound from the vibratory member to pass the diaphragm,

and a cylindrical tube, open at the outer end,

attached to said diaphragm-inside said openmgs.

4. In a sounding device, the combination of a shallow vibratory member with resilient top and-bottom walls, means for subjecting said members to pneumatic suction,and a valve to relieve said suction secured to one of said walls, a diaphragm against which said valve seats, and a valve for controlling the pneumatic suction,-said valve of small area compared with the relief valve area.

5. In a sounding device, the combination of a resilient diaphragm, a bellows device made up of disk members secured together at the edges, an air conduit communicating with the inside of the said bellows, a valve for one of the disks of. the bellows device, said valve adapted to seat against the resilient diaphragm, and means for creating a partial vacuum within the bellows device through the air conduit whereby the bellows device will contract, the valve will be unseated, the vacuum destroyed and the valve will return to its seat.

6. In a sounding device, the combination of a sound projecting device, a diaphragm, means for mounting said diaphragm at the rear of the projecting device, with air passages betweenthe diaphragm and the in terior of the horn, a resilient diaphragm set facing the first mentioned diaphragm, said latter diaphragm being energized to act as a motor by the creation of a vacuum, and

a valve mounted in said motor, diaphragm, and adapted to seat against the diaphragm firstmentioned, and an enclosing member mounted on this diaphragm around the air passages, for the purpose described.

WALTER A. GARRATT. 

